James a



(No Model.)

J. A. ROBERTS.

OUTTER HEAD.

No. 811,679. Patented Feb. 8, 1'885.

wyrywa-r Nrrnn 'rarns rrrciro lfarnn'r JAMES A. ROBERTS, OF DETROIT,MIOHIGAN, ASSIGNOR TO THE ROBERTS DUPLEX PLANING MACHINE TOOL COMPANY,OF SAME PLACE.

CUTTER-HEAD.

SPECIPICATION formng part of Letters Patent No. 311,679, dated February3, 18185.

Application filcd September 17, 1884.

I'o all whom it may conccrn:

Be it known that I, J AMEs A. RoBnR'rs, of Detroit, iii the county .ofVayne and State of Michigan, have invented'new and useful Improvementsin Cutter-Heads; and I hereby declare that the following is a full,clear, and eX- act description thereof, reference being had to theaccompanying drawings, which form a part of this specification.

Io This invention relates io an improvement in the construction of andmeans for securing tools to cutter-heads, and theinvention is morespecifically intended to apply to the cutterheads of a planing andinatching machine for [5 which I have heretol'oreapplied for LettersPatent.

The invention consists in the combination' of the beading and tonguingknives with retaining-caps for securing each one to the cutzo tor-head,said caps being recessed in conformity to the cutting-faces of saidknives, as more fully hereinafter set forth and claimed.

In the drawings, Figure 1 is a perspeetve View of two cutter-heads, withplaning, tonguing, and beading knives secured thereto and shown inoperation; and Fig. 2 is a sectional detail of the same.

A is the ordinary cutter-head in present use in planing-niachines.

B are tonguing-knives, intended to form a tongue upon the inner edges ofthe boards O, which are separated by a division-plate, D.

E are other knives, intended to round the inner edges of the tongues.

F are beading-knives for making the usual center bead in ceiling, and Gare the ordinary planer-knivcs.

The planer-knives are of the ordinary description, and are secured tothe cutter-head in the usual way. The tonguing and beading knives are ofuniform cross-section throughout, the cutting-face of saidcross-section, being of any desired configuration varying from astraight line, so that when the tool is ground in the usual manner thecutting-edge shall present just the required outline.

H are caps for securing the tonguing and beading tools in place upon thecutter-head without the use of slots in the tools. These caps arerecessed upon their under side in eX- (No model.)

l act conforinity with the shape of the knife, the recess, however,being made a trifle shallower, so that when the caps are secured bymeans of the bolts I and nuts J the caps will clamp the knives to thecutter-head. The bolt I is pro- Vided with a head, K, by which it isretained in the lateral grooves L of the cutter-head.

The afore described construction of the knives and the manner ofsecuring them in place has the advantage that the cutter-head may alwayscarry all the necessary knives for making either fiooring or ceiling..Those knives which are not used for one of the two Operations may bemade inoperative by loosening the nut J, rctracting the knife, and thenti ghtening the nut again. Another advantage is that the knives are fitfor use until. there is nothing but a short stump of the material left,while with the ordinary construction a good deal of material is wastedby the knife becoming soon too short for use by repeated grinding.

I am aware that it is not new to secure beading-knives to cutter-headsby a recessed retaining-cap and bolt, the head of said bolt running inan undercut groove in the face of the cutter-head, and I do not claimsuch as my invention, for iii all such constructions that I ani aware ofthe recess in the retaining-cap has not been in conformity to the shapeof the Cutting-face of the knife when the latter has said face varying:from a straight line running crosswise thereof. The disadvantage ofthis construction is that where the retaining-cap only contacts with theelevated or raised portions of the cutting-face ofthe tool saidportionsbecome marred and unfit for use, and the tool cannot be usedthroughout its entire length, and, besides, the tool is more liable toslip when in operation, thereby causing a serious delay or destructionof property. All these obj ections are eliminated by my improvement,

as the retaining-cap is recessed to fit the contour of the cutting-faceof the knife, thereby causing a contacting of every element of the twosurfaces and affording a large frictional contact, thus avoiding amarring or spoiling of the Cutting-face of the tool and overcomin theliability of its slipping.

What I ola-im as my invention is-- ICO of the Cutting-face of the knife,all construct- The combination of a ontter-head having y ed and arrangedsubstanti'lly'as described, undercnt lateral grooves 01' rnortises uponits l whereby an inoreased frietion'ftl surface is se- Io face, the nutJ, retaining-bolt I, and a knife I oured between the tool and Cap, asset forth. havinw its acting face Varying from a straight line aduniform in cross-section thronghout JAMES A' ROBER FS' its whole length,with a retaining-cap reoessed VVitnesses: upon its under side inoonformity to the Shape WILLIAM M. DWIGHT,

A. O. OARTER.

